Before he became an award-winning and world-renowned director, 'Hugo's'Martin Scorsese had slightly more humble film beginnings. Actually, a lot more humble. One of those early efforts was 'Boxcar Bertha,' a gritty crime exploitation film set along the railroads of Depression-era America. To the young and naive Scorsese, the film was a big deal, but it was just another B-movie in a long list of B-movies for its producer Roger Corman.

Corman, one of the most prolific filmmakers in history, also served as a mentor to directing powerhouses like James Cameron and Francis Ford Coppola; before they became the talent behind the biggest movies in history, Corman put them through his patented "cheap and fast" school of film production. In this new clip from the upcoming documentary 'Corman's World: Exploits of a Hollywood Rebel,' Martin Scorsese reveals just how little he actually knew when it came to making a movie with Roger Corman.

'Corman's World: Exploits of a Hollywood Rebel' will arrive in select theaters on December 16.